1. Download and install Mantid from [here](http://download.mantidproject.org/) ensure that you take the official latest release.
1. Open the [MantidPlot](https://www.mantidproject.org/MantidPlot:_General_Concepts_and_Terms) Grapical User Interface which came with your Mantid installation and open the [script window](http://docs.mantidproject.org/v3.7.2/interfaces/ScriptingWindow.html)